Some work machines, such as a small wheel loader or backhoe loader, have a boom arrangement with a coupler pivotally attached thereto. The boom arrangement often includes a boom having a boom pivot point at an end portion of the boom for pivotally connecting a coupler to the boom. In such an arrangement, the boom pivot point often defines a horizontal axis of rotation for the coupler. Additionally, the boom arrangement may be provided with a linkage configured to rotate the coupler about this horizontal axis. In these work machines, the coupler, which is connected to the boom and linkage arrangement, provides a mechanism for coupling a variety of different work tools to the work machine.
Oftentimes, the coupler is provided with work tool connection points, wherein the work tool is attached to the coupler. These work tool connection points are usually offset a distance from the boom and linkage pivot points. These offset distances may create a mechanical disadvantage for the work machine, if the offset distances are great. If the work tool is a bucket, for example, and as the offset increases, more force is required from the boom and machine linkage to carry a constant bucket load. As the lifting capacity of the work machine decreases, the work machine productivity may also decrease.
In an effort to overcome this working disadvantage, some work machines are designed with stronger lifting arrangements and with larger power plants, which often results in increased cost to make and sell the work machine.
One example of such a coupler is disclosed in U.S. Pat. No. 5,382,110 to Perotto et al. (“Perotto”). In Perotto, a quick coupling device adapted for mounting a tool to a boom of a carrier is provided.
Further, in other work machines, the operator may need to securely attach the work tool to the work machine by manually pinning the work tool to the coupler. In these machines, productivity decreases as the operator spends more time coupling and decoupling work tools.
The present invention is directed to overcoming one or more of the problems as set forth above.